Hello,
A friend of mine told me about this guy, Dr.Ray Peat, and how he followed his eating recommendations and said his health has improved quite a bit. H, he talks about avoiding fish oils, eating cheese, meat and especially about thyroid issues. On the website there is an article section, I wanted your opinion on what this guys says. I know it's kind of generic, but just for thought. Also, he advises to stay away from grains, nuts and seeds. I don't know there so much confusing info online..

http://raypeat.com/
I am not impressed with his information. First of all he is relying heavily on animal studies that do not correlate to humans. I looked at some of his references and did not see how was was even extrapolating his claims from those references. But one of the best was in an article on fish oil in which he used a rabbit study to back his claim that fish oil promoted plaque formation in humans. Here is the reference he used:

Food Chem Toxicol. 1998 Aug;36(8):663-72.
The association of increasing dietary concentrations of fish oil with hepatotoxic effects and a higher degree of aorta atherosclerosis in the ad lib.-fed rabbit.

The long-term effects of consumption of marine long-chain n-3 polyunsaturated fatty acids (PUFA) on atherosclerosis in the rabbit were examined. Female Dutch rabbits were fed purified diets, containing 40 energy% total fat, for a period of 2.5 years. To study the dose response relationship between fish oil intake and atherosclerosis, four diets were formulated with fish oil levels being 0, 1, 10 and 20 energy%. A fifth and sixth group were fed an alpha-linolenic acid-(C18:3, n-3) and linoleic acid-(C18:2, n-6) rich diet, respectively. Every 6 weeks, blood samples were taken for determination of clinical chemical parameters, triacylglycerol and total cholesterol levels. Feeding 10 and 20 energy% fish oil containing diets, resulted in an increase of liver enzymes (AST, ALT and ALP). Histological evaluation of the liver also revealed adverse effects of fish oil containing diets. Triacylglycerol blood levels were similar in all groups, and remained constant throughout the study. Total cholesterol levels in blood was significantly lower in the animals fed a linoleic acid-rich diet, as compared with the other five groups. An n-3 long-chain PUFA concentration dependent increase in aorta plaque surface area was observed in the fish oil groups. A significant positive relationship was found between the group mean score for severity of liver pathology and the aorta plaque surface area. These results indicate that the long-chain n-3 polyunsaturated fatty acids in fish oil may be hepatotoxic to the herbivorous rabbit, which may interfere with the outcome of atherosclerosis studies. This finding necessitates the exclusion of liver pathology in experimental studies on atherosclerosis in animal models.

Does he really think that rabbits, who are vegetarians would have adapted to metabolizing high levels of fish oil like humans have?!!!

One of the reasons animals are used so often in research is that particular animals can be chosen to get the desired outcome for a study. If I wanted to prove that chocolate is deadly all I would have to do is to feed pure chocolate to a dog, which will overload their nervous system. So can I extrapolate from this that chocolate is deadly to humans based on its toxicity in dogs? Of course not. But this is exactly what this guy is doing in his articles. He is looking for animal studies that will back what he believes even though these do not automatically apply to humans.

I also find it interesting how he is trying to promote coffee as being healthy when in fact it can crash the adrenals leading to a number of problems including hypothyroidism, although he claims it helps the thyroid. Coffee can also block iron, which he mentions, but claims this can prevent iron overload. Yes, but this also means it can induce anemia. Coffee can also block the absorption of other nutrients and medications. Then there is the fact that it can contribute to gout, inflammation, cancers, insomnia, etc. So he is showing a very twisted view of the supposed health benefits of coffee.
As far as his claim about coffee supporting the thyroid, this is partially true, but this also brings up another one of his mistakes. There is a compound produced by the body known as cyclic adenosine monophosphate (cAMP) that is needed for proper thyroid function. The author claims that coffee raises cAMP levels, which is not true. It can prevent cAMP breakdown though. Coffee contains caffeine, theophylline and theobromine that block the enzyme cyclic adenosine monophosphate phosphodiesterase (cAMPPDE) that breaks down cAMP. This is the same reason an old time remedy for an asthma attack is a strong cup of coffee. Among other effects cAMP also blocks histamine and leukotrienes that are involved in the triggering of asthma. So by blocking cAMP breakdown the coffee can help stop an asthma attack.

On the other hand the effects on asthma and the thyroid are with occasional use. With consistent use the person will crash their adrenals. This can lead to allergies/asthma, fatigue, hypotension, hypothyroidism, water imbalances, increased inflammation, immune suppression including autoimmunity, hormone imbalances, etc.

We would also be in major disagreement when it comes to hormones as he feels hormone therapy is safe and I do not.

I also find it interesting that he bases the medical community for not differentiating between synthetic progestins and progesterone. Apparently he is unaware that the progesterone compounds he recommends also happen to be synthetics. Nobody offers natural progesterone on the market. The so-called "bio-identicals are synthesized from the plant sterols just like their pharmaceutical counterparts.